JPS62123427A - Active matrix liquid crystal display element and its production - Google Patents

Abstract

PURPOSE:To raise an effective voltage applied to a liquid crystal to reduce a driving voltage by packing the liquid crystal material between a matrix substrate provided with display electrodes, thin film transistors TRs, scanning lines, and signal lines and a counter substrate provided with counter electrodes divided in the scanning direction into a prescribed number with respect to the number of scanning lines. CONSTITUTION:Scanning lines 102 and signal lines 103 are provided on a matrix substrate 101, and thin film TRs 104 are provided at intersections and the connected to display electrodes 105. A counter substrate 106 having counter electrodes 107 which are divided in the scanning direction into n/x [(n) is the number of scanning lines, and (x) is 1, 2,...,n/2 and can divide (n) without a remainder] is provided to face the substrate 101, and the liquid crystal material is sealed between substrates. A video signal is inputted from an input terminal 108 and is applied to TRs 104 through a video control circuit 109 and X and Y drivers. Meanwhile, a counter electrode signal is applied to electrodes 107 through a counter electrode driver 113 to display data on the liquid crystal.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an active matrix type liquid crystal display element provided as a thin film transistor all-switching element at the intersection of a scanning line and a signal line, and a method for manufacturing the same. .

(Conventional method) Compared to conventional simple matrix devices, active matrix liquid crystal display devices are capable of large-screen clear display and can improve display characteristics (contrast, viewing angle, number of gradation levels), so research on active matrix liquid crystal display devices is underway. is becoming more active. In recent years, O
There is a high demand for it as a display element for A equipment, and expectations for its development are also increasing.

Among the active elements provided in active matrix liquid crystal display devices, thin film transistors have high reproducibility and manufacturing yield. In particular, thin film transistors using amorphous silicon or polysilicon thin film are used for IC,
It is considered to be promising because it is improved by T and SI technology and can be applied to all nine semiconductor manufacturing processes. Even now, examples using amorphous silicon thin film transistors are excellent.
ATIONAL C0NF'ERgN(J ON CO
C0N5U'gLEcTRONIcs Record)
1984, p. 74.

A general perspective view of the structure of an IJ Fuchs crystal display element is shown in FIG. 4. Pass lines of scanning lines 402 and signal lines 403 are wired in a matrix on an IJ7 substrate 401 using an insulating substrate such as glass, and two thin film transistors (T
['T) 40 = 1 are provided in the matrix, and are electrically connected to the scanning line 402, the signal line 403, and the immersion electrode 405 in the matrix. A counter substrate 406 which is provided opposite to the matrix substrate 401 and has a counter electrode 407 is sealed with a liquid crystal between the substrates, and the matrix substrate 40
1 and is bonded with a sealant.

Here, the counter electrode 407 is provided over the entire surface of the counter substrate 406 in an area larger than the display surface.

In addition, there are cases in which the extraction terminals of the opposing TA electrodes are provided on the matrix substrate 401 side with the transfer electrodes all valved.Furthermore, a color filter for color display is installed on the top or bottom of the oncoming vehicle. In some cases, it is provided in

To produce display sound, a video signal is input from the input terminal 408. The input video control circuit 409 generates a scanning signal, which is determined based on the frame period, the number of scanning lines of the display element, the scanning method, etc.

A video signal sampled according to the display capacity of the fc display element is also generated by the video control circuit 409.
A voltage is also created to be applied to the counter electrode to apply the full electric field to the liquid crystal. When displaying in color, a sampling signal as a color signal is generated through the entire color separation circuit. In order to fully drive the scanning line side of the display element, the scanning signal is further subjected to signal processing by a shift register biasing X-direction driver 410, and then applied to the TPT gate connected to the scanning line 402 of the display element. In the case of display by line sequential scanning, the video sampling signal is processed by a Y-direction driver 411 which has a sampling hold circuit in addition to a shift register and can hold 1947 minutes, and is processed by a TPT drain connected to the signal line 403 of the display element. (or source). The voltage applied to the oncoming vehicle t4i 407 is also referred to as a common opposing voltage (VCOM) 412 because it acts commonly on all display electrodes. As described above, the scanning line 402 and the signal line 403 of the active matrix display element and the common facing 1! Voltages are applied to the L poles 412 according to the display pattern, allowing any pixel in the matrix to be displayed.

The voltage applied to generate the display sound will be explained in detail using the signal charts of FIGS. 5 and 6.

An example using amorphous silicon TPT'fr will be described. Field period to scan one screen 'rFn+c
10 to 2 with a total pulse width corresponding to the number of scanning lines nK
The total gate voltage is about 0V, and the first scanning line is V. 1,
VG on the first scanning line, V on the Sth scanning line. n
Apply each in the following order. Regarding one signal line,
Looking at the 'rFn' signal between fields Jt and Jl,
Synchronize with the timing when all the scanning lines are scanned, and set the position to be displayed, for example, vDl for the first position, vDl for the first position,
vDl for the th location, vDn for the nth location
When applying a maximum drain (or source) voltage of about 15 to 20 V to the signal line and displaying all gradations, lO ~
The voltage is applied while varying the '1 pump pressure value within the range of 20V.

However, when using a field-effect liquid crystal material, the properties of the liquid crystal material will deteriorate if the electric field in a single direction changes over many years, so an alternating electric field is applied to the liquid crystal material in consideration of the lifespan of the liquid crystal material. . Therefore, the common counter voltage V
It is applied as COM, and the reference level of its drain (or source) voltage is also the same as VCOM. Then, in the next field period TFn+1, all the typing devices are placed in the display area, and the previous field period TFn is reversed.
I + vDI + vDn': set to zero. As a result, an electric field in the opposite direction is applied to the liquid crystal for each field period, and display is performed by applying an electric field in the opposite direction to the liquid crystal. (containment pressure) and no electric field is applied to the liquid crystal.

For example, a display electrode provided at the intersection with a certain signal line on the n-th scanning line and a liquid crystal material having a capacitance t are placed opposite to each other.
The liquid crystal applied voltage vL generated between the fugitive electrodes is charged by the absolute value of l VDn 'COM' by the switching of TF'T and becomes vLl. Even after TPT is turned off, VLoTri is discharged and attenuated due to the CR time constant seen from the liquid crystal side, but the OFF' resistance of TF'T is 10"Q
Because the resistance of the liquid crystal itself is high, and the resistance of the liquid crystal itself is similarly high, the time constant is attenuated or suppressed to about 40% during the field period.

As mentioned above, in conventional active matrix liquid crystal display elements, to apply an alternating electric field to the liquid crystal, the total application voltage is X/2 of the signal voltage to the common electrode. It had the disadvantage of being twice as expensive.

By the way, a method can be considered in which the entire alternating voltage is applied to the common electrode as well. However, using positive and negative alternating voltages has the disadvantage that a separate negative power supply is required, as in the case where the signal voltage uses positive and negative alternating voltages. As another method, without using a separate negative power supply, the drain (or no,
p VDll YC7E positive alternating 1 every de period
When the display is turned on, a full reverse voltage is applied, and a full alternating direct voltage opposite to the signal voltage is applied to one common opposing voltage VCOM every field period of a positive alternating voltage.
Increase the effective voltage applied to the liquid crystal.1. One possibility is to lower the driving voltage. However, in this method as well, the driving on the first scanning line can obtain the liquid crystal applied voltage vLn as ideally described above, but the liquid crystal applied voltage vLn on the n-th scanning line can be obtained.
Fi, the above-mentioned TPT Ro FF resistance, liquid crystal resistance, liquid crystal capacitance, and storage capacitors that may be added have almost no effect, and the potential of the counter electrode immediately reverses after the nth scan. V in Figure 6 to change
Like Lo, the width of the voltage applied to the liquid crystal is short, the effective voltage is small, and the liquid crystal cannot be turned on completely, which has the disadvantage of being impossible.

Therefore, the conventional active matrix liquid crystal display element in which the opposing WX is a single common electrode has an unavoidable problem of driving voltage due to its structure, which cannot be solved by changing the driving method to some extent.

In addition, in the manufacturing process of the conventional active matrix display element, the counter electrode provided on the counter substrate 406 acts on all the display electrodes 405 of the matrix substrate 401 in common, as described above, so that the counter electrode is larger than the display surface. It is provided all over the area. Also, for this reason, in the process of bonding the matrix substrate 401 and the counter substrate 406, alignment between the display electrode 405 and the counter X pole 407 is not performed, and the electrodes are extended from the counter electrode 407 to the matrix substrate 401 via the transfer electrode. All you need to do is align the tiger/sphere electrodes when connecting them to the electrodes.

(Problems to be Solved by the Invention) The active matrix liquid crystal display device having the above structure and manufacturing method requires a high driving voltage in order to obtain the best contrast, viewing angle, and number of gradations. There is a need,
Therefore, there was a drawback that a power source capable of obtaining high voltage was required. Since the required current is small, the power consumption is low even when the voltage is high (although there is one advantage, the use of a voltage power supply imposes restrictions on the driver IC, restrictions on the battery used, etc., and there are overall system disadvantages.) becomes.

Also, the fact that there is a separate negative power source is also a drawback of the system.
This increases the amount of heavy electricity required, making it unsuitable for hand belt systems.

It should be noted that a structure of an active matrix liquid crystal display element to solve these drawbacks has not been proposed so far, nor has a method of manufacturing the same been proposed.

(Object of the Invention) Therefore, the object of the present invention is to provide an active material that can increase the effective voltage applied to the liquid crystal and lower the driving voltage than before.
The present invention provides a J Fuchs crystal display element and a method for manufacturing the same.

(Tth Means for Solving the Problem) According to the first invention of the present application, there is provided a matrix substrate in which nine display electrodes, thin film transistors, scanning lines, and signal lines are provided in a matrix, and a matrix substrate having nine scanning lines. For n, two opposing substrates are divided into n/x pieces in the scanning direction and provided with nine opposing electrodes (x = 1.2.3..., a number that is 1° and n can be divided into an integer). An active matrix liquid crystal display element characterized in that a liquid crystal material is filled between substrates can be obtained.

According to the second invention of the present application, in the method for manufacturing an active matrix liquid crystal display element, the steps include: providing nine counter electrodes divided into a plurality of pieces on a counter substrate on which a counter electrode is provided; and a step of providing a display electrode, a thin film transistor, and a scanning electrode. A matrix substrate in which wires and signal lines are provided in a matrix, respectively, and the above-mentioned counter substrate are aligned between the gap between the counter electrode lines on the counter substrate and the above-mentioned bus line, using the pass line of the scanning line on the matrix substrate as alignment. There is obtained a method of manufacturing an active matrix liquid crystal display element, which comprises the step of laminating the substrates in substantially the same manner.

(Function) In the active matrix liquid crystal display element of the present invention, the counter electrode provided on the counter substrate is
Divide the number of scanning lines of the IJ Fuchs plate by a divisible number and divide it into 9 lines. After the n-th scan, even if the first scan is performed, the n-th
The voltage applied to the liquid crystal can be maintained with the time constant of CR. As a result, the voltage applied to the liquid crystal can be improved by a total of twice that of the conventional one.

Therefore, in a system using the active matrix liquid crystal display element of the present invention, it is possible to use a low power supply voltage, and the system can be driven by a normal dry cell battery, making it possible to use a hand belt system.

Further, the voltage of the driver circuit that obtains the display can also be reduced, making IC design extremely easy.

Furthermore, in the method for manufacturing an active matrix liquid crystal display element of the present invention, in the step of laminating the IJ Fuchs plate and the counter substrate, the pass line of the scanning line of the matrix substrate is used for alignment, and the counter electrode on the counter substrate is By aligning the line gaps and the scan line pass lines so that they almost match, a spatial phase shift with respect to the liquid crystal is unlikely to occur between the voltage applied to the display electrodes and the voltage applied to the counter electrode. . In addition, alignment K by this manufacturing method takes advantage of the fact that the scanning line is a metal wiring that does not transmit light.
Another advantage is that alignment can be performed using transmitted light. Therefore, it can be implemented without significantly complicating the conventional lamination process.

(Example) Hereinafter, an example of the present invention will be described with reference to all the drawings.

(Example 1) Figure 1 illustrates the entire structure of the embodiment of the first invention of the present application.
1 is a schematic full perspective view of an active matrix liquid crystal display element.

In FIG. 1, like the conventional example, a matrix substrate 10
1, a scanning line 102 and a signal line 103 are provided, and a thin film transistor (TPT) 104 is provided near the intersection thereof, connected to a display electrode 105, and arranged in a matrix. This matrix substrate 10
A counter electrode 1 that is provided opposite to the counter electrode 1 and divided into a plurality of hydraulic pressure parts.
A counter substrate 106 having a substrate 07 is filled with a liquid crystal material between the substrates and is bonded to the matrix substrate 101 with a sealant.

Here, since the number of scanning lines provided on the matrix substrate is 400, the counter electrode is a divided counter electrode lo7 divided into 400 lines. The length of the divided counter electrode 107 is longer than the display surface. Moreover, the divided counter electrode 10
The output terminal 7 may be provided not on the opposing substrate 106 but on the side of the matrix substrate 101 opposite to the scanning line extension terminal with all the transfer electrodes. Furthermore, a color filter for displaying a curl may be provided above or below the counter electrode.

To obtain a display, a video signal is input from the input terminal 108, and the video control circuit 109 generates a scanning signal and an image sampling signal to be applied to the signal line, as in the conventional case. Similarly, the TPTs in the matrix are subjected to processing and applied as gate and drain (or source) voltages. However, the voltage of the counter electrode, which conventionally applies a constant voltage to the entire surface of the element, is not used here. Counter electrode signal 112
can receive a trigger from the scanning period of the scanning line 102 of the matrix substrate 101. Further, by the trigger, a voltage is sequentially applied to the divided counter electrodes 107 via a counter electrode driver 113 having a shift register that processes signals. Scanning of the counter electrode and ma) +3
The scanning of the display electrodes 105 in the Tx substrate 101 is synchronized. As a result, liquid crystal display can be performed using the 1050 ratio display electrodes selected for the scanning line 102 and the signal line 103, as in the prior art.

By the way, in the case of an active matrix liquid crystal display device according to the present invention, a signal as shown in FIG. 2 is used, and the drain (or source) voltage applied to the signal line is alternated every field period, and The voltage applied to the electrodes is alternated with a field period for each scan;
The liquid crystal applied voltage VLI on the th scanning line is also
Both i and the last nth vLn can have the same effective voltage.

Therefore, conventionally the effective voltage t-2 applied to the liquid crystal
It was possible to double the number of drives, and the total drive voltage could be lowered by that amount. This reduces the conventional drain voltage 'j
It can convert 10~20V to 5~12V, allowing normal dry battery operation. Also, since the drain current depends not only on the gate voltage but also on the drain voltage,
As the effective value of the drain voltage increases, the gate voltage can also be lowered. Furthermore, since the voltage of the IC used in the driver circuit can be reduced, it is extremely easy to design an IC for processing 12V signals compared to conventional ICs that process signals of up to 20V.

Furthermore, since the alternation of the potentials of the divided opposing electrodes is a field period, a low frequency may be used.

In the above case, the counter electrode is divided into the same number as the number of scanning lines on the matrix substrate, but depending on the time constant when the liquid crystal is turned off, the scanning time, and the number of scanning lines, the number of divisions may be changed, such as dividing it into about half the number of scanning lines. It is possible to change.

(Example 2) FIG. 3 is a schematic diagram showing a method of manufacturing an active matrix liquid crystal display element for explaining the method of the embodiment of the second invention of the present application, and (a) is a plan view of the element. (b) shows a part of a cross-sectional view of the element on the broken line in figure a1 of the element.

In FIG. 3, a scanning line 302, a signal line 303, and a TFT
The matrix substrate 301 on which the display tWL 304 and display tWL30s are provided is divided into a plurality of pieces, and the next divided counter electrode 307
A scanning line terminal (not shown), a signal line terminal 314, and a counter electrode terminal 315 are stacked so as to be exposed on a counter substrate 306 provided with a counter substrate 306. In this state, light is irradiated to see through the element. Since the scanning line is a metal wiring, it does not transmit light and appears as a black line. Using this black scanning line for alignment, the opposing electrode gap 317'i
Move one of the boards to match it. Apply the sealant 31 to one of the substrates in a matched state, and then apply the sealant 31
6 to adhere and laminate the side substrates together. The difference from the conventional method of manufacturing an active matrix liquid crystal display element is that, prior to the above-mentioned bonding process, the substrate 30 is
Although a step of dividing the counter electrode provided in step 6 into a plurality of pieces is required, after forming the conductive thin film for the counter electrode, patterning may be performed using a well-known photo process or the like.

Further, the other manufacturing steps are the same as those of the well-known prior art.

As described above, in the 7'CW manufacturing method according to the present invention, alignment between the scanning line and the divided counter electrodes is easy, and no positional shift occurs, so no phase shift occurs in the voltage applied to the liquid crystal. . Furthermore, since this manufacturing method requires only relatively easy alignment, the total cost i increases very little compared to the conventional substrate bonding process.

(Effects of the Invention) As explained in detail above, the active matrix liquid crystal display element of the present invention can be driven at a low voltage, facilitates normal dry battery operation, and has a voltage comparable to that of a dry battery. However, since a sufficient effective value of the voltage applied to the liquid crystal can be obtained, the display characteristics are also improved. Furthermore, since the voltage of the driver circuit IC attached to the display element can be reduced, its design is easy. Furthermore, since it requires a lower voltage power supply than before and does not require two power supplies,
It becomes easier to apply the hand belt system.

In addition, in the manufacturing method in which the present invention is fully implemented, the assembly process of the display element is easy, and the total cost does not increase. Further, since there is no misalignment between the scanning line and the divided counter electrode, accurate display and display with good display characteristics can be obtained for hydrogen atoms during production.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of an active matrix liquid crystal display element for fully explaining the structure of an embodiment of the first invention of the present application, and FIG. FIG. 3 is a schematic diagram showing the bonding process of the next method of manufacturing an active matrix liquid crystal display element, which will be fully explained in accordance with the embodiment of the second invention of the present application, and FIG. A schematic diagram showing the structure of a general active matrix liquid crystal display element, and FIGS. 5 and 6 are charts of signals applied to the conventional display element. Figure 3 (al is a part of the plan view of the display element, (b) is (
In a schematic diagram showing a part of a cross-sectional view taken along a breaking line of al, 101, 301, 401 are matrix substrates;
2,302,402 is a scanning line, 103.303,403
is a signal line, 104,304°404FiTFT, 105
, 305, 405 are display electrodes, 106, 306, 406
is a counter substrate, 107°307Fi divided counter electrode, 407
is the counter electrode, 108°408 is the input terminal, 109,40
9 is a video control circuit, 112 is a common electrode signal, 113 is a common electrode driver, 311 is a signal line terminal, 315 is a common electrode terminal, 3161'! A sealant, 317 a gap between opposing electrodes, 410 an X-direction driver, 411 a Y-direction driver, and 412 a common counter voltage gold. 2nd I! I Knee Figure 5

Claims (1)

[Claims] 1. A matrix substrate in which display electrodes, thin film transistors, scanning lines, and signal lines are each provided in a matrix, and the number n of scanning lines of the matrix substrate is divided into n/x lines in the scanning direction. counter electrode (x=1, 2, 3..., n
1. An active matrix liquid crystal display element, characterized in that a liquid crystal material is filled between two substrates, including a counter substrate provided with a number of n/2 and n divisible by an integer. 2. In the method for manufacturing an active matrix liquid crystal display element, a step of providing a counter electrode divided into a plurality of lines on a counter substrate on which a counter electrode is provided, and a step of providing a display electrode, a thin film transistor, a scanning line, and a signal line in each matrix. The matrix substrate and the opposing substrate are aligned using the bus line of the scanning line on the matrix substrate,
1. A method of manufacturing an active matrix liquid crystal display element, comprising the step of bonding the counter electrode lines on the counter substrate so that the gap between the counter electrode lines and the bus line substantially coincide with each other.